interesting hardware.. :
http://www.xs4all.nl/~marcmarc/ele/signrig/index.html
http://www.xs4all.nl/~marcmarc/ele/fff/index.html
http://www.xs4all.nl/~marcmarc/ele/4mvca/index.html
http://www.xs4all.nl/~marcmarc/ele/cd333/index.html
very special machines can be found here..
for converting and lots more.. maybe interesting for modular systems and very special systems..
site of Marc Marc (scroll!!)
http://www.xs4all.nl/~marcmarc/ele/index.html